Is it possible to cover the whole spectrum, high SPL, low distortion with a 2-way?

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#1,281
Audio Elite said:
The compression driver use a 2.5-inch diaphragm with a 1.4 inch throat featuring several state of the art technologies. The diaphragm and suspension are formed from 0.05mm thick pure titanium
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I have to disappoint you, the diaphragm is nothing special.
I would go as far to say it's the weak spot in the driver.
 

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#1,282
docali said:
From which speaker are these measurements?

We see about 12dB descent from 90Hz down turning into 18dB from 50Hz on. No bass fundament at all... The frequency response taken only at 80dB Level... Huge break-up modes at HF. A very strong beaming with deep holes. The distortion curves end at 5k while fr response is shown up to 40k - why? The answer might be the steep increase of distortions at the right side.

I would not waste any money in such a design in the sense of this thread searching for a reference Monitor design.
Click to expand...

These are from the Martion Bullfrog. Probably (semi) anechoic conditions (Stereo Magazin).
I agree with you. This is a bass-shy loudspeaker and should be used with subs, as I already stated a few pages ago.
In some rooms it may touch 60Hz -6dB or so, but that's about it.
 
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#1,285
More marketing BS:

"Coaxial drivers are perfect point sources. This one is even better. A 1.5 inch compression driver made entirely from titanium with a pure titanium membrane fires into a horn that is crafted from special fibers and offers a perfect radiation with no unwantanted sweet spot and a crystal clear sound due to its practically vibration free material. The horn sits in the middle of a glorious 15inch bass driver made from poplar wood fibres, acoustically treated to minimize reflections."

It accompanies this loudspeaker, that uses the same RCF coax.

standmonitor-15hc-6-810x420@2x.jpg


Hilarious specs:
Efficiency: 100 db SPL/1W/1m
Frequency Range: 29 Hz – 22.000 Hz

This guy soaks both diaphragm and cone in Shellac... works wonders :wiz:

Nevertheless, I read some some show reports in which the highs are described as 'stingy'.



Anybody with a little knowledge of loudspeaker technology, or audio in general, ought to steer clear from high-end culture.
High-end, with a few exceptions, is targeted at people with - preferably lots of - cash to burn and a 'black-box syndrom' to cherish.
 
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#1,294
The 18" in that 60 grand a pair Tobian 2-way might as well be a RCF anyway, assuming this guys prefers to buy from a single manufacturer and thus receive considerable discounts.

Currently, RCF's line-up lacks an 18" with M-roll surround and ribless cone. However, the good 'ol budget L18P300 fits the picture perfectly.

011_l18p300_gallery.jpg
 
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#1,295
GM said:
OK, I thought this horn driver is what the 1.4" initially referenced: https://www.diyaudio.com/forums/att...l-low-distortion-2-a-bullfrog_old-drivers-jpg

GM
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At first glance you'd think Altec 288/291. The terminals are different though.
The top (underside in the pic.), including the terminals, looks like vintage JBL.

Funny thing is, about a 1.5 ago I was close to buying a set of vintage drivers that looked exactly like this.
Even though these were almost free of charge I let them pass, because the dias were gone.
Some time later I coincidently stumbled upon the driver online, but can't recall the brand now. It'll pop up sooner or later.
 
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#1,296
docali said:
From which speaker are these measurements?

We see about 12dB descent from 90Hz down turning into 18dB from 50Hz on. No bass fundament at all... The frequency response taken only at 80dB Level... Huge break-up modes at HF. A very strong beaming with deep holes. The distortion curves end at 5k while fr response is shown up to 40k - why? The answer might be the steep increase of distortions at the right side.

I would not waste any money in such a design in the sense of this thread searching for a reference Monitor design.
Click to expand...

I know you are right. At first sight/thoughts its nice to imagine that everything I could want can be put into such a tight coaxial package. I am happy with the product I am in progress with now =)
Just received an email, my 16ohm AE TD15M order is being processed...no idea what that means but!, they'll be here when they get here =)
Can you believe that I still haven't settled on verticle vs horizontal lol! If I do it right I'll be able to reconfigure it, at will.
I did conclude that a front cover is mandatory. Too much money to stand in front of a 2 year old. When I leave for work, I can put the door on, put my keyboard away, all is well. =/
 
#1,299
vuki said:
18 Sound

Their drivers sound very nice in Duevel loudspeakers (omnidirectional 2-way horn/woofer)
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Thanks! Last time I paid attention, 18 Sound was a startup with a few relatively inexpensive woofers, but quite the lineup now, though unfortunately saw no 1.4" to sub/replace Altec/GPA. 🙁

I don't get out much, so thanks for listing the Duevals; looks like something I'd like to audition, but apparently no USA outlet. 🙁

GM
 
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